If you use an aerosol whipped cream like Reddi-Wip, the air will deflate much sooner than if you whip your own stabilized whipped cream.

Even if you don’t stabilize the whipped cream, your own beater-whipped cream will stay fluffy longer. You don’t need to create whipped cream stars, which the Reddi-Wip nozzle enables. Instead, just emulate the real white bars of the flag, and use one long line of whipped cream in-between the rows of strawberries.